地质学报2017，Vol.91Issue(11)：2573-2583,11.
准噶尔盆地哈山地区石炭系-二叠系裂缝充填方解石的成因机制及石油地质意义
Genetic Mechanism of Calcite Veins in Carboniferous-Permian Volcanic Reservoirs in the Hashan Area, Junggar Basin and Its Petroleum Geological Significance
摘要
Abstract
The Hashan area in the NW margin of the Junggar Basin experienced multiple phases of intense tectonic movements,with fissures well developed in Carboniferous and Permian systems and most filled with calcite.This study discussed formation fluid activity and its relationship with hydrocarbon accumulation using analyzing the geochemical features of carbon,oxygen and strontium isotopes,and fluid inclusion of fillings from calcite veins.The results indicate that calcite fillings are generally influenced by both volcanic hydrothermal fluid and oil source fluids.δ13C feature reflects that mantle and atmosphere were two sources for the carbon elements in calcite,and negative characteristics of δ18O mainly reflects the influence of high temperature fluid medium,and the ratios of 87Sr/86Sr means that it was affected by both the mantle-derived strontium and crust-derived strontium.Comprehensive analysis suggests that there were three genetic mechanisms for formation of calcite veins:volcanic hydrothermal,petroleum-derived fluid,and meteoric water,each of which corresponded to Carboniferous and Permian volcanic hydrothermal fluid activity,oil-sourced fluid since late Permian,and meteoric water in late period.The homogenization temperatures of the secondary hydrocarbon-bearing brine inclusions developed in calcite fillings are distributed in three temperature ranges:70～80℃,100～110℃ and 130～160℃,corresponding to three phases (Late Permian,Late Triassic,Late Cretaceous) of oil-source fluid charging,respectively.Among them,the Permian oil-sourced fluid made important contribution to Carboniferous and Permian hydrocarbon accumulation.关键词
方解石脉/碳氧锶同位素/流体包裹体/石炭系二叠系/准噶尔盆地哈山地区Key words
calcite vein/carbon, oxygen and strontium isotopes/fluid inclusion/Carboniferous-Permian systems/Hashan area in the Junggar Basin引用本文复制引用
刘勇,袁海锋,高耀,赵永福,徐国盛..准噶尔盆地哈山地区石炭系-二叠系裂缝充填方解石的成因机制及石油地质意义[J].地质学报,2017,91(11):2573-2583,11.基金项目
本文为“十二五”国家重大科技专项“准噶尔盆地碎屑岩层系大中型油气田形成规律与勘探方向”(编号2011ZX05002-002)资助成果. （编号2011ZX05002-002）
